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Nanotechnology in a Nutshell Christian Ngô • Marcel Van De Voorde Nanotechnology in a Nutshell Christian Ngô • Marcel Van de Voorde Nanotechnology in a Nutshell From Simple to Complex Systems Christian Ngô Marcel Van de Voorde Edmonium Faculty of Applied Sciences Saint-Rémy-lès-Chevreuse DELFT University of Technology France The Netherlands Image Courtesy H. DAWSON, Ch. ABERG, M. MONOPOLI, University College Dublin (Ireland). The picture on the cover page of the book represent: Nanoparticle protein corona engaging with a cellular receptor. ISBN 978-94-6239-011-9 ISBN 978-94-6239-012-6 (eBook) DOI 10.2991/978-94-6239-012-6 Library of Congress Control Number: 2013953213 Ó Atlantis Press and the authors 2014 This book, or any parts thereof, may not be reproduced for commercial purposes in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system known or to be invented, without prior permission from the Publisher. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Foreword Science and technology are engines of progress in society. They are also of increasing interest to the general public, consumers, and policy makers, in addition to scientists and economists. New ground for science policy was broken in January 2000, when the then President Clinton announced the National Nanotechnology Initiative driven by a 20-year vision. Nanotechnology currently is well recognized as a science and technology megatrend for the beginning of the twenty-first cen- tury. This book aims to show where nanotechnology is now––transitioning to complex systems and fundamentally new products—and communicates the soci- etal promise of nanotechnology to specialists and the public. All materials we see around us have a nanostructure that determines their behavior. Because of nanotechnology—control of matter at the atomic, molecular, and macromolecular levels where specific phenomena enable novel applications— major industries and medicine are changing. Advances at the nanoscale are leading to new understanding of nature and manmade things, and an increased ability to restructure matter at the atomic and molecular levels. The multidisciplinary field of nanotechnology has been expanding since 2000 in large public and private programs around the world, reaching an annual global investment in 2012 of approximately $20 billion. Most of what has already made it into the marketplace is in the form of ‘‘First Generation’’ products (passive nanostructures with steady behavior, such as coat- ings, nanoparticles, nanowires, and bulk nanostructured materials). Many small and large companies have ‘‘Second Generation’’ products (active nanostructures with changing behavior during use, illustrated by transistors, amplifiers, targeted drugs and chemicals, sensors, actuators, and adaptive structures) and embryonic ‘‘Third Generation’’ products (nanosystems, including three-dimensional nanosystems using various synthesis and assembling techniques such as bio-assembling; nanoscale robotics; networking at the nanoscale and multiscale architectures; after 2010) in the pipeline. Concepts for ‘‘Fourth Generation’’ products, including het- erogeneous molecular nanosystems, are only in research. Each generation of new products is expected to include, at least partially as components, products from previous generation. The labor and markets are estimated to double every 3 years, reaching a $3 trillion market encompassing 6 million jobs by 2020 if one assumes that the rates of increase in the last 12 years would continue. Nanotechnology has the promise to create a basic understanding and a general purpose technology with v vi Foreword mass and sustainable use by 2020 (‘‘Nanotechnology Research Directions for Societal Needs in 2020’’, Springer, 2011, www.wtec.org/nano2/). While expectations from nanotechnology may have been overestimated in the short term, the long-term implications on health care, productivity, and the envi- ronment appear to be underestimated. This volume will stimulate further interest and bring faster societal recognition to nanotechnology and overall to emerging technologies. Mihail C. Roco Senior Advisor for Nanotechnology National Science Foundation Arlington USA Reference M. C. Roco, C. A. Mirkin, and M. C. Hersam, ‘‘Nanotechnology research and directions for societal needs in 2020’’, Springer, 2011 Presentation of the Book It is rare for a new technology to transform all aspects of human activity. In history, one can identify agriculture, the industrial revolution, and the advent of personal computing as truly unprecedented advances. In the twenty-first century, nanotechnology is predicted to provide the next revolution. Nanotechnology spans all of our human activity, from agriculture, medicine and food to clothing, from transport to industrial processes. It is not just about the ability to understand and manipulate material at the nanoscale, it is the way in which a new technology will be used to change the way products are made and to provide a step change in the functionality that they provide. Nanotechnology has been a part of many commonplace products for hundreds of years. Steel, concrete, adhesives, and cosmetics have all used nanoscale mechanisms to achieve their properties, but developments have historically been through craft skills and trial-and-error rather than through science and engineering. Recent developments in experimental techniques that allow the study and manipulation of materials at the nanoscale, coupled with novel manufacturing techniques, mean that we are poised to be able to realize new properties and functions that previously could not be achieved. One nanometer (nm) is one millionth of a millimeter (mm) or/and a billionth of a meter. As a matter of comparison, ants range in size from 2 to 25 mm and a red blood cell has a size around 6,000–8,000 nm. Ultimately, all living and inert matter is made of atoms, which have a dimension well below the nanometer range, typically a diameter between 0.1 and 0.65 nm = 100 and 650 pm (1 pm = picometer). An atom is made of electrons surrounding a nucleus whose diameter is even smaller: its size is about 1.8–15 millionths of a nanometer depending upon the element (1.8–18 fm)! Table 1 recalls the different subunits used as we go from the visible macroscopic world to the microscopic world. A nanometer is quite a small length scale. In order to imagine a 1 nm compared to 1 m ( = 109 nanometers) which is a billion larger, let us consider two large distances in our solar system: the distance from the earth to the moon (*360,000 km) and the distance to the sun (*150 millions of km). If we shrink these distances by a factor of 109 we get 36 cm for the first distance and 150 m for the second one. The radius of the sun (*696,000 km) becomes 69.6 cm and that of the earth (6,400 km) becomes equal to 6.4 mm. These comparisons show that a vii viii Presentation of the Book Table 1 Units and subunits Unit Value in meter Value in meter 1 m (meter) 1 m 100 m 1 centimeter (cm) 0.01 m 10-2 m 1 millimeter (mm) 0.001 m 10-3 m 1 micrometer or micron (lm) 0.000 001 10-6 m 1 nanometer (nm) 0.000 000 001 10-9 m 1 picometer (pm) 0.000 000 000 001 10-12 m 1 femtometer (fm) 0.000 000 000 000 001 10-15 m Fig. 1 Dividing a cube into nanocubes increases the total surface of the system a lot nanometer distance is quite a small distance compared to those we are faced at the macroscopic level. Compared with macroscopic systems, surface effects are very important at the nanoscale. The reason for this can be illustrated by considering a cube of side 1 cm, as shown in Fig. 1. The total surface area of this cube is six faces each of dimensions 1 9 1 cm, making a total of 6 cm2. Suppose we divide this cube into small cubes of side 1 nm (Fig. 1). This gives the incredible number of 1021 nanocubes each with a tiny surface area of 6 9 10-14 cm2. However, the total area of these nanocubes amounts to 6,000 meters squared! This corresponds to the surface area of 60 houses of 100 m2. This demonstrates the power of surfaces at the nanoscale. Strictly speaking, nanotechnology should concern building objects from the bottom-up using atoms or molecules. It also makes possible a top-down approach of reducing size and organization from the macroscopic scale. However this vision is extended to a broader domain where it is possible to observe, see, detect, move, and manufacture objects with dimensions in the range of 1–100 nm. This is much less restrictive and opens a wide field of applications, some of them being already on the market. Presentation of the Book ix Fig. 2 Illustration with objects of different length scale and instruments that can be used to observe them On the other hand, ‘‘nanomaterials’’ is a term used to describe a broad and disparate range of materials containing characteristic features with dimensions below 100 nm. It is the properties of these individual nanoscale features and their organization both at the nanoscale and up to the macroscale that will define the properties of nanomaterial. These features can be organized in random or well- ordered patterns. Confusingly, a ‘‘nanomaterial’’ can be of macroscopic size containing many nano-objects but it can also be an individual object investigated as a material at the nanoscale. A nanomaterial can be a thin film, a thin wire, or a collection of nanoparticles, for example. A nanomaterial is often characterized by a dimension linked either to the dimension of the salient nanofeatures making up the material or to their organization. When some interesting property of a material emerges from this organization or pattern, the combined material may be referred to as a ‘‘nanostructure’’ or a ‘‘nanostructured material’’.
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